Timing device



V. TRAD TIMING DEVICE June 17, 19 52 5 Sheets-Sheet 1 Filed July 24, 1946 JNVEN'I'OR;

ATTORNEYS,

V. TRAD TIMING DEVICE June 17, 1952 5 Sheets-Sheet 2 Filed July 24, 1946 June 17, 1952 v. TRAD 2.601,010

TIMING DEVICE Filed July 24, 1946 5 Sheets-Sheet s INVEN'I'OR.

/2069?" Iiad ATTORNE 115',

Patented June 17, 1952 UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to timing devices such asare used on coin operated electrical appliances.

An object of this invention is to provide an inexpensive timing device for coin operated appliances.

Another object of this invention is to provide a timing device which shall be responsive to the value of the coin inserted.

A further object of this invention is to provide a simplified timing device which shall be small enough to fit within the cabinet of an appliance and operate efiiciently.

A feature of the invention is the small number of moving parts required for its operation.

The invention consists of the construction, combination and arrangement of parts, as herein illustrated, described and claimed.

In the accompanying drawings, forming part hereof, are illustrated three forms of embodiment of the invention, in which drawings similar reference characters designate corresponding parts, and in which:

Figure 1 is a diagrammatic view of the coin timing device, great1y enlarged.

Figure 2 is a fragmentary view of a solenoidactuated cam.

Figure 3 is a diagrammatic view of a second form of the timing mechanism.

Figure 4 is a view in elevation of the structure shown in Figure 3, with certain hidden parts shown in dotted lines.

Figure 5 is a diagrammatic view of a third form'of the invention.

Figure 6 is a plan view of the friction finger of the embodiment of the invention shown in Figure 5.

Referring to the drawings, and particularly to Figure 1, I0 indicates an electrically conductive cogwheel having a plurality of teeth thereon. The trough between two of the teeth II on the wheel I0 is covered by a suitable electrically non-conductive material I2.

A hand operated push rod I3, having a pawl M at the end thereof, is mounted so that it is engageable with the cogwheel ID. The rod I3 is returned to its original position and removed from contact with the wheel when not in use by means of a coil spring H5.

The power necessary to rotate the cogwheel I0 is provided by a solenoid IS, an armature H, a bi-metal switch 22, and the circuit associated therewith. The solenoid I6 is positioned slightly below the cogwheel |0 and connected in parallel with the source of electrical potential l8. The armature I! is supported by a coil spring I9 and floats freely within the solenoid IS. The upper end of the armature terminates in an electrically conductive arm 20 to the end of which is attached an electrically conductive spring hinged pawl 2|. The function of said pawl 2| is to engage the teeth ll of the wheel ID in a hereinafter described manner.

A bi-metal conductor 22 or some electronic timing device is inserted in series with the solenoid l6, so as to periodically interrupt the current flowing therethrough. If a bi-metal conductor 22 is employed, a heating coil 24 may be connected in parallel with the circuit, as shown in Figure 1, to provide the heat necessary to actuate the said bimetal 22.

The operation of the coin operated timing mechanism becomes apparent from the foregoing description, and an examination of Figure 1. When a coin is inserted in the receiving slot, not shown, of the timer, the push rod l3 may be forced down. The pawl 4 on the end of the rod l3 engages a tooth H of the cogwheel IB and rotates the wheel one station. Prior to this movement, the wheel l0 was at rest, with the pawl 2| of the armature touching the insulated teeth l2. As soon as the cogwheel ID is moved from this position, the pawl 2| makes electrical contact with the wheel teeth The current flows from the input terminal |8 to the armature l1 and its pawl 2|, and then to the wheel H]. A spring finger 21, riding upon the hub 28 of the wheel I0, conducts this current to the appliance 26. The heating coil 24 of the bimetal contact 22, connected in parallel across the two input lines 23, 29 leading to the appliance 26, heats up. The bimetal 22 is connected to the input line 23. A contact point 22a, positioned near the free end of the bimetal 22 is connected to the line leading to the solenoid 16. As the coil 24 heats the bimetal 22 it bends and makes contact with the contact point 22a, and the current flows through this path of less resistance. The solenoid I6 thereupon becomes energized and draws the armature ll downward.

While the current is flowing through the bimetal 22 the coil 24 cools down until the bimetal straightens and breaks contact. At that instant the current flows through the coil 24 again and the solenoid 6 becomes de-energized. The armature within the solenoid I6 is forced upward by the spring l9 when the solenoid is shut off. The pawl 2| at the end of the arm 20 then engages a succeeding cogwheel tooth II. The cycle is repeated in this manner until the pawl 2| springs into the trough between the insulated teeth I2.

The insulation prevents the current from flowing through the cogwheel ID to the appliance 26 and stops the operation of the said appliance.

It then becomes necessary to force the wheel I past this station to resume the timing cycle. It is clear that the length of time during which the appliance 26 may be operated depends upon the interval required for the cogwheel H) to make a 360 revolution. The time interval is governed by the nature of the bimetal 22 and its heating coil 24, and also by the number of teeth in the cogwheel or the number of insulated stations thereon.

Another embodiment of this invention is shown in Figures 3 and 4, in which 39 is a cogwheel similar to that shown in Figure l. A ratchet cam 3| is mounted upon a pivot 32 adjacent to the wheel 30 and engageable therewith. The cam detents 33, 34 are so arranged as to impart a continuous rotary motion to the wheel 39 when the cam 3| is reciprocated upon the pivot 32. The cam 3| receives its motion from a bimetal 35 which is secured thereto by a coupling 36. The bimetal 35 is actuated by a heating coil 31 therearound.

When a coin is inserted in the coin chute 38 and the plunger 39 depressed, it closes a switch 40. The switch is closed in this manner since the coin slides down the chute 38 until it comes to rest upon the pin 74. The plunger 39 then bears against the coin to push down the pin 14 and the arm 15 to which it is attached. The arm I carries with it the linkage 16 which is connected to the switch lever '11. The thrust of the plunger 39 thus overcomes the pull of the spring 18 and closes the said switch 40. This enables a voltage to flow to appliance 42 from the current source 4|. A portion of the electrical potential also passes through the bimetal resistance coil 31. As the coil 31 heats the bimetal 35 it flexes downward because of the unequal expansion of the metal plates therein. This motion causes the cam 3| to turn upon the pivot 32. The detent 33 is thereupon slowly removed from the teeth of the wheel 30 while detent 34 is forced into contact with the said wheel 30. This causes the wheel 30, shown in Figures 3 and 4, to move in a counterclockwise direction.

A contact point 43, attached to the end of a spring finger 44 touches the crest of the cog wheel teeth. The spring finger 44 is tangentially located with respect to the cogwheel I0 and is electrically connected to the end of the heating coil 31. One terminal 45 of a switch 46 is mounted upon the upper edge of the finger 44. As the cogwheel 30 turns and the contact 43 slips from the crest of the tooth, the finger 44 is released and springs downward. The contact of the terminals 45, 41 is thereupon broken and the current ceases to flow through the heating coil 37. As the bimetal 35 cools it straightens and returns the cam 3| to the position shown in Figure 2. The cam 3| turns upon the pivot 32 during the cooling process, causing the detent 33 to engage a succeeding tooth on the cogwheel 30 and continue the counterclockwise rotation of the said wheel.

As soon as the crest of the next tooth touches the contact 43, the switch 45 is closed and the current again flows through the coil 31 to continue the cycle. is caused to rotate at a specific rate of speed.

An arm 48 is attached to the cogwheel 30. When the wheel 3|) has completed one revolution the arm 48 pushes against a pivotally mounted switch release 49. This action breaks the con- In this manner the cogwheel 30 tact at the switch 40 which was closed by the coin controller plunger 39. The voltage passing through the timer and the appliance is thereupon out.

The release lever 49 and the contact of the switch 40 are balanced by springs 50, 5| best shown in Figure 4. These springs 50, 5| enable the release 49 to open the switch 40 with a minimum of effort.

It is within the purview of this invention to use this timer with or without the use of a coin as, for example, where it is desired that an appliance not be used unnecessarily. It is also possible to limit the amount of operating time by providing the cogwheel with more than one release arm 49, so that a complete revolution of the said wheel will not be necessary before the switch is opened.

The solenoid l6, shown in Figure 1, and the cam 3|, shown in Figures 3 and 4, may be combined into a simplified acutating mechanism as illustrated in the fragment of Figure 2 of the drawings. The cam 3| is pivoted at 12 and provided with a small pin 13 in the middle of the said cam 3|. The pin 13 rides on the armature H of the solenoid l6. As the armature rises it lifts the pin 13 and thereby causes the cam 3| to turn upon the pivot 12. When the armature l1 drops it returns the cam 3| to the position shown in Figure 2. A spring finger T4 is provided on the end of the cam 3| to facilitate engagement with the teeth H of the cogwheel H). A circuit similar to that shown in Figures 1 or 3 may be used in conjunction with this mechanism.

Where it is desired to further save space, the cogwheel |0 may be replaced by a straight, toothed member 52, as shown in Figure 5. In this embodiment of the invention the toothed member 52 is provided with a plurality of teeth 53 along one of its sides. A longitudinal slot 54 is cut into the said toothed member so that the entire member 52 may ride upon a pivot 55 projecting therethrough. A bimetal 56 is positioned next to the toothed member 52 so that its free end engages the teeth 53. The bimetal 56 is heated by a resistance coil 57 therearound when the timer is in operation.

When a coin is inserted in the chute, not shown. it depresses a plunger 58 which in turn closes a contact release switch 59. This allows the current to flow from the source of electrical potential 60 to the appliance 6|. The current also flows through the coil 51 which is connected in parallel with the power supply. As the coil heats up it causes the bimetal 56 to bend upward, thereby lifting the toothed member 52. When the free end of the bimetal reaches the pin 62 mounted upon the sliding plate 63, it lifts the said plate 63. The contact pin 64 mounted upon the plate 63 is thereupon pulled away from the contact terminal 65 and the circuit to the heating coil 5! broken. As the coil 51 cools, the bimetal 56 straightens out until the sliding plate 63 drops sufiiciently to establish the electrical contact between the pin 64 and the terminal 65. The free end of the cooling bimetal 56 slips past the crest of the next tooth 53, the said toothed member 53 pivoting laterally for this purpose, as indicated by dotted lines in Figure 5.

A spring 66 urges the toothed member 52 back against a fixed pin 6'! and into a vertical position, as soon as the bimetal 56 clears the tooth 53. The toothed member 52 is prevented from sliding downward during the cooling portion of the cycle by reason of friction fingers 68, shown in plan in Figure 6, which fingers grasp it at all times.

As the resistance coil 51 heats up again, the bi-metal 5B begins to curve upward to repeat the cycle. In this manner the toothed member is raised until a release pin 69 mounted on the edge of the toothed member 52 strikes the switch release arm 10. The release arm then breaks the main circuit, causing the flow of current to the appliance to be interrupted. The trip pin 69 is positioned so that it will strike the release arm 10 when the bimetal is in the cooling cycle, that is, as the toothed member 52 is swung out on its pivot 55. It is apparent that the time interval may be varied by changing the location of the pin 69 on the toothed member 52.

When it is desired to start the apparatus again it will be necessary to restore the toothed member 52 to its original position, shown in Figure 5. A plunger H is shown for this purpose, which bears against one corner of the toothed member 52 so that it will be caused to swing clear of the free end of the bimetal 56 as it travels downward. It is to be understood that the plunger H may be coupled to the coin plunger 58 for simplification of design.

Having thus fully described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States, is:

1. A timing device comprising, a cogwheel, a rockably mounted cam adjacent said cogwheel, spaced detents having a fixed interval therebetween carried by the cam alternately engageable with the cogwheel teeth, a bimetal strip coupled to the cam, a heating coil around the said strip, said coil being incorporated into an electrical circuit adapted to energize the coil and actuate the bimetal to rock the cam, thereby rotating the cogwheel and means carried by the cogwheel to stop its rotation after a predetermined interval.

2. A timing device comprising, a cogwheel, a rockably mounted cam adjacent said cogwheel, spaced detents having a fixed interval therebetween carried by the cam alternately engage- 6 able with the cogwheel teeth, a bimetal strip coupled to the cam, a heating coil around the said strip, said coil being incorporated into an electrical circuit adapted to periodically energize the coil and actuate the bimetal to rock the cam, thereby rotating the cogwheel and means carried by the cogwheel to stop its rotation after a predetermined interval.

3. A timing device comprising, a cogwheel, a rockably mounted cam adjacent said cogwheel, spaced detents having a fixed interval therebetween carried by the cam alternately engageable with the cogwheel teeth, a bimetal strip coupled to the cam, a heating coil around the said strip, said coil being incorporated into an electrical circuit adapted to energize the coil and actuate the bimetal to rock the cam, thereby rotating the cogwheel, a switch in series with the said electrical circuit having one arm thereof in contact with the teeth of the cogwheel, whereby said switch will be alternately opened and closed as the wheel rotates and means carried by the cogwheel to stop its rotation after a predetermined interval.

VICTOR TRAD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 393,132 Wagner Nov. 20, 1888 1,438,789 Schon Dec. 12, 1922 1,519,568 Van Amstel Dec.16,1924 1,795,013 Denman Mar. 3, 1931 1,893,348 Anderson Jan. 3, 1933 2,009,601 Anderson July 30, 1935 2,315,920 Baker Apr. 6, 1943 2,427,207 Grieveson Sept. 9, 1947 2,487,154 Lloyd Nov. 8, 1949 FOREIGN PATENTS Number Country Date 312,104 Great Britain Mar. 21, 1929 

